Revealing the working mechanism of a multi-functional block copolymer binder for lithium-sulfur batteries

作     者：Xin He Zhimeng Liu Guoping Gao Xiaotao Liu Michal Swietoslawski Jun Feng Gao Liu Lin-Wang Wang Robert Kostecki Xin He;Zhimeng Liu;Guoping Gao;Xiaotao Liu;Michal Swietoslawski;Jun Feng;Gao Liu;Lin-Wang Wang;Robert Kostecki

作者机构：Energy Storage&Distributed Resources DivisionLawrence Berkeley National Laboratory1 Cyclotron Road94720 BerkeleyUSA Materials Sciences DivisionLawrence Berkeley National Laboratory94720 BerkeleyUSA The Molecular FoundryLawrence Berkeley National Laboratory94720 BerkeleyUSA Department of Materials Science&EngineeringSouthern University of Science and Technology(SUSTech)Shenzhen 518055China 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2021年第30卷第8期

页      面：1-8,I0001页

核心收录：

学科分类：081702[工学-化学工艺] 0808[工学-电气工程] 08[工学] 0817[工学-化学工程与技术] 

基　　金：supported by the Assistant Secretary for Energy Efficiency and Renewable Energy,Vehicle Technologies Office,under the Advanced Battery Materials Research(BMR)Program of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231 support by the U.S.Department of Energy under Contract No.106298-001 the funding from Polish Ministry of Science and Higher Education No.1670/MOB/V/2017/0 funding support of SUSTech the resources of the National Energy Research Scientific Computing Center(NERSC)that is supported by the Office of Science of the U.S.Department of Energy 

主　　题：Lithium sulfur batteries Polymer binder Block copolymer Ultraviolet-visible spectroscopy X-ray absorption spectroscopy 

摘      要：The lithium-sulfur(Li-S)battery is one of the most promising substitutes for current energy storage systems because of its low cost,high theoretical capacity,and high energy ***,the high solubility of intermediate products(i.e.,lithium polysulfides)and the resultant shuttle effect lead to rapidly fading capacity and a low coulombic efficiency,which hinder the practical application of Li-S *** this study,block copolymers are constructed with both an ethylene oxide unit and a styrene unit and then used as binders for Li-S *** performance improvements are attributed to the synergistic effects contributed by the different units of the block *** ethylene oxide unit traps polysulfide,which bonds strongly with the intermediate lithium polysulfide,and enhances the transport of lithium ions to reach high ***,the styrene unit maintains cathode integrity by improving the mechanical properties and elasticity of the constructed block copolymer to accommodate the large volume *** enabling multiple functions via different units in the polymer chain,high sulfur utilization is achieved,polysulfide diffusion is confined,and the shuttle effect is suppressed during the cycle life of Li-S batteries,as revealed by operando ultraviolet-visible spectroscopy and S Kedge X-ray absorption spectroscopy.